Influence of sulphuric acid contaminants on Fricke dosimetry.

abstract：:For PET online data acquisition, a centralized coincidence processor (CCP) with a single-thread data processing has been used to select coincidence events for many PET scanners. CCP has the advantage of highly integrated circuit, compact connection between detector front-end and system electronics, and centralized con...

journal_title：Physics in medicine and biology

authors： Cheng X,Hu K,Yang D,Shao Y

更新日期：2021-01-21 00:00:00

abstract：:Absorption and emission optical projection tomography (OPT), alternatively referred to as optical computed tomography (optical-CT) and optical-emission computed tomography (optical-ECT), are recently developed three-dimensional imaging techniques with value for developmental biology and ex vivo gene expression studies...

journal_title：Physics in medicine and biology

authors： Fumene Feruglio P,Vinegoni C,Gros J,Sbarbati A,Weissleder R

更新日期：2010-09-21 00:00:00

abstract：:A non-contact approach for diffuse optical tomography (DOT) has been developed for on-demand image updates using surgical navigation technology. A stereoscopic optical tracker provides real-time localization of reflective spheres mounted to a laser diode and near-infrared camera. Standard camera calibration is combine...

journal_title：Physics in medicine and biology

authors： Daly MJ,Wilson BC,Irish JC,Jaffray DA

更新日期：2019-07-05 00:00:00

abstract：:As a prerequisite for clinical treatments it was necessary to characterize the Elekta 1.5 T MRI-linac 7 MV FFF radiation beam. Following acceptance testing, beam characterization data were acquired with Semiflex 3D (PTW 31021), microDiamond (PTW 60019), and Farmer-type (PTW 30013 and IBA FC65-G) detectors in an Elekta...

journal_title：Physics in medicine and biology

authors： Woodings SJ,Bluemink JJ,de Vries JHW,Niatsetski Y,van Veelen B,Schillings J,Kok JGM,Wolthaus JWH,Hackett SL,van Asselen B,van Zijp HM,Pencea S,Roberts DA,Lagendijk JJW,Raaymakers BW

更新日期：2018-04-19 00:00:00

abstract：:Patient motion is an important factor affecting the quality of external beam radiotherapy in breast patients. We analyse the motion of a dense set of surface points on breast patients throughout their treatment schedule to assess the magnitude and stability of motion, in particular, with respect to breast volume. We u...

journal_title：Physics in medicine and biology

authors： Price GJ,Sharrock PJ,Marchant TE,Parkhurst JM,Burton D,Jain P,Price P,Moore CJ

更新日期：2009-11-07 00:00:00

abstract：:The in vivo electric conductivity (σ) values of tissue are essential for accurate electromagnetic simulations and specific absorption rate (SAR) assessment for applications such as thermal dose computations in hyperthermia. Currently used σ-values are mostly based on ex vivo measurements. In this study the conductivit...

journal_title：Physics in medicine and biology

authors： Balidemaj E,de Boer P,van Lier AL,Remis RF,Stalpers LJ,Westerveld GH,Nederveen AJ,van den Berg CA,Crezee J

更新日期：2016-02-21 00:00:00

abstract：:Conventional molecular assessment of tissue through histology, if adapted to fresh thicker samples, has the potential to enhance cancer detection in surgical margins and monitoring of 3D cell culture molecular environments. However, in thicker samples, substantial background staining is common despite repeated rinsing...

journal_title：Physics in medicine and biology

authors： Xu X,Wang Y,Xiang J,Liu JTC,Tichauer KM

更新日期：2017-06-21 00:00:00

abstract：:We investigated the physical characteristics of two complementary metal oxide semiconductor (CMOS) mammography detectors. The detectors featured 14-bit image acquisition, 50 microm detector element (del) size and an active area of 5 cm x 5 cm. One detector was a passive-pixel sensor (PPS) with signal amplification per...

journal_title：Physics in medicine and biology

authors： Elbakri IA,McIntosh BJ,Rickey DW

更新日期：2009-03-21 00:00:00

abstract：:The bone suppression technique based on advanced image processing can suppress the conspicuity of bones on chest radiographs, creating soft tissue images obtained by the dual-energy subtraction technique. This study was performed to evaluate the usefulness of bone suppression image processing in image-guided radiation...

journal_title：Physics in medicine and biology

authors： Tanaka R,Sanada S,Sakuta K,Kawashima H

更新日期：2015-05-21 00:00:00

abstract：:A classical trajectory model has been used to predict total cross sections of single and double ionizing processes (including capture processes) for several ion-biological molecule collisional systems in the intermediate and high energy range. In this work, the systems studied are water, adenine or cytosine targets io...

journal_title：Physics in medicine and biology

authors： Abbas I,Champion C,Zarour B,Lasri B,Hanssen J

更新日期：2008-02-21 00:00:00

abstract：:This note describes a simple phantom which can be used to check the long term stability and accuracy of relative attenuation measurements made by near infra-red (NIR) spectrometers. The phantom has been calibrated, and the results of the calibration are shown to agree with theoretical predictions of the relative atten...

journal_title：Physics in medicine and biology

authors： Firbank M,Delpy DT

更新日期：1994-09-01 00:00:00

abstract：:The design, construction and use of a large-scale field-cycled proton-electron double-resonance imaging (FC-PEDRI) imager is described. The imager is based on a whole-body sized, vertical field, 59 mT permanent magnet. Field cycling is accomplished by the field compensation method, and uses a secondary, resistive magn...

journal_title：Physics in medicine and biology

authors： Lurie DJ,Foster MA,Yeung D,Hutchison JM

更新日期：1998-07-01 00:00:00

abstract：:A single experimental apparatus has been designed to allow measurements of stopping cross-sections of materials in liquid and vapour phase, for alpha particles, using an indirect method. The method, in which residual energies for increasing absorber thicknesses are obtained and differentiated, has been used in a numbe...

journal_title：Physics in medicine and biology

authors： Thwaites DI

更新日期：1980-09-01 00:00:00

abstract：:The purpose of this work was to validate GATE-based clinical scale absorbed dose calculations in nuclear medicine dosimetry. GATE (version 6.2) and MCNPX (version 2.7.a) were used to derive dosimetric parameters (absorbed fractions, specific absorbed fractions and S-values) for the reference female computational model...

journal_title：Physics in medicine and biology

authors： Villoing D,Marcatili S,Garcia MP,Bardiès M

更新日期：2017-03-07 00:00:00

abstract：:An algorithm for dynamic multileaf-collimator (dMLC) tracking of a target performing a known a priori, rigid-body motion during volumetric modulated arc therapy (VMAT), has been experimentally validated and applied to investigate the potential of the Agility (Elekta AB, Stockholm, Sweden) multileaf-collimator (MLC) fo...

journal_title：Physics in medicine and biology

authors： Davies GA,Clowes P,Bedford JL,Evans PM,Webb S,Poludniowski G

更新日期：2013-07-07 00:00:00

abstract：:This work compared the impact of x-ray tube performance and automatic dose rate control (ADRC) parameter selection on system imaging efficiency of two Siemens angiography systems: a Siemens Megalix x-ray tube installed on an Artis Zee system (denoted 'MEGALIX') and a newer generation Gigalix x-ray tube installed on an...

journal_title：Physics in medicine and biology

authors： Dehairs M,Bosmans H,Marshall NW

更新日期：2020-11-24 00:00:00

abstract：:New values of the factors required to convert the reading of a radiation dosemeter calibrated in terms of air kerma (or exposure) into absorbed dose to water for medium-energy x-radiation were given in a code of practice published by the IAEA in 1987. These are not considered to possess sufficient support from other s...

journal_title：Physics in medicine and biology

authors：

更新日期：1991-08-01 00:00:00

abstract：:Data filtering is crucial for accurate relative stopping power (RSP) reconstruction in proton CT (pCT). In this work, we assess different filters and their performance for the US pCT collaboration prototype pCT system in Monte Carlo (MC) simulations. The potential of using the recently proposed [Formula: see text]-E f...

journal_title：Physics in medicine and biology

authors： Volz L,Piersimoni P,Johnson RP,Bashkirov VA,Schulte RW,Seco J

更新日期：2019-08-01 00:00:00

abstract：:Flow visualization, particle image velocimetry and numerical computation have been complementarily performed to study the fluid flow inside a stented lateral aneurysm. The curved afferent vessel had an inner diameter of 5 mm. The diameters of the aneurysmal orifice, neck and fundus were 7 mm, 5 mm and 7.5 mm, respecti...

journal_title：Physics in medicine and biology

authors： Liou TM,Li YC,Wang TC

更新日期：2008-07-21 00:00:00

abstract：:The purpose of this study is to develop an adaptive prior knowledge guided image estimation technique to reduce the scan angle needed in the limited-angle intrafraction verification (LIVE) system for 4D-CBCT reconstruction. The LIVE system has been previously developed to reconstruct 4D volumetric images on-the-fly du...

journal_title：Physics in medicine and biology

authors： Zhang Y,Yin FF,Zhang Y,Ren L

更新日期：2017-05-07 00:00:00

abstract：:Despite over ten years of in vitro investigations of ultrasound contrast agents, the level of understanding of their behaviour in ultrasound fields is limited. Several problems associated with these investigations, particular to the nature of contrast agents, are discussed. Using a commercial scanner the RF normalized...

journal_title：Physics in medicine and biology

authors： Sboros V,Ramnarine KV,Moran CM,Pye SD,McDicken WN

更新日期：2002-12-07 00:00:00

abstract：:The quality of radiation therapy delivered for treating cancer patients is related to set-up errors and organ motion. Due to the margins needed to ensure adequate target coverage, many breast cancer patients have been shown to develop late side effects such as pneumonitis and cardiac damage. Breathing-adapted radiatio...

journal_title：Physics in medicine and biology

authors： Kakar M,Nyström H,Aarup LR,Nøttrup TJ,Olsen DR

更新日期：2005-10-07 00:00:00

abstract：:Exploiting the field response of magnetic tracers, magnetic particle imaging (MPI) allows direct, local quantification of the tracer concentration in bulk structures. Here, we investigated the use of characteristic field response functions to spatially resolve the absolute concentration of multiple nanoparticle specie...

journal_title：Physics in medicine and biology

authors： Han SH,Cho E,Lee DK,Cho G,Kim YR,Cho H

更新日期：2014-11-07 00:00:00

abstract：:Currently, energy spectra of laser accelerated proton beams are far from being monoenergetic. For their application in radiation therapy, energy selection systems using magnetic fields have been proposed to single out particles with the desired energy. These systems allow the choice of protons between a lowest and a h...

journal_title：Physics in medicine and biology

authors： Schell S,Wilkens JJ

更新日期：2009-10-07 00:00:00

abstract：:The metabolic content of urine from NIH III nude mice (n = 22) was analysed before and after inoculation with human glioblastoma multiforme (GBM) cancer cells. An age- and gender-matched control population (n = 14) was also studied to identify non-tumour-related changes. Urine samples were collected daily for 6 weeks,...

journal_title：Physics in medicine and biology

authors： Moroz J,Turner J,Slupsky C,Fallone G,Syme A

更新日期：2011-02-07 00:00:00

abstract：:The UK, European and IAEA protocols for breast dosimetry in mammography use tabulations of conversion factors, which relate measurements of incident air kerma to the mean glandular dose to the breast. To supplement the existing tabulations, a Monte Carlo computer program has been used to calculate conversion factors f...

journal_title：Physics in medicine and biology

authors： Dance DR,Young KC

更新日期：2014-05-07 00:00:00

abstract：:A new thin-target method (patent pending) is described for portal imaging with low-energy (tens of keV) photons from a medical linear accelerator operating in a special mode. Low-energy photons are usually produced in the accelerator target, but are absorbed by the target and flattening filter, both made of medium- or...

journal_title：Physics in medicine and biology

authors： Tsechanski A,Bielajew AF,Faermann S,Krutman Y

更新日期：1998-08-01 00:00:00

abstract：:The performance of a light sharing and recirculation mechanism that allows the extraction of depth of interaction (DOI) are investigated in this paper, with a particular focus on timing. In parallel, a method to optimize the coincidence time resolution (CTR) of PET detectors by use of the DOI information is proposed a...

journal_title：Physics in medicine and biology

authors： Pizzichemi M,Polesel A,Stringhini G,Gundacker S,Lecoq P,Tavernier S,Paganoni M,Auffray E

更新日期：2019-08-07 00:00:00

abstract：:Ultrasound current source density imaging (UCSDI) exploits the acoustoelectric (AE) effect, an interaction between ultrasound pressure and electrical resistivity, to map electrical conduction in the heart. The conversion efficiency for UCSDI is determined by the AE interaction constant K, a fundamental property of all...

journal_title：Physics in medicine and biology

authors： Li Q,Olafsson R,Ingram P,Wang Z,Witte R

更新日期：2012-10-07 00:00:00

abstract：:Amorphous silicon electronic portal imaging devices (EPIDs) are used to perform routine quality control (QC) checks on the multileaf collimators (MLCs) at this centre. Presently, these checks are performed at gantry angle 0 degrees and are considered to be valid for all other angles. Since therapeutic procedures regul...

journal_title：Physics in medicine and biology

authors： Clarke MF,Budgell GJ

更新日期：2008-01-21 00:00:00